Mount Etna, Europe's most active volcano, spews lava during an eruption, near the Sicilian town of Catania, southern Italy, early Tuesday, February 28, 2017. The eruption was not dangerous and the airport of Catania is still open and fully operating. (Photo by Salvatore Allegra/AP Photo)

Oroville Dam's crippled spillway is inspected via helicopter after it was shut off Monday, February 27, 2017, in Oroville, Calif. California water authorities stopped the flow of water down the dam's spillway allowing workers to start clearing out massive debris that's blocking a hydroelectric plant from working. (Photo by Paul Kitagaki Jr./The Sacramento Bee via AP Photo)

Counselor to the President Kellyanne Conway (L) checks her phone after taking a photo as US President Donald Trump and leaders of historically black universities and colleges pose for a group photo in the Oval Office of the White House before a meeting with US Vice President Mike Pence February 27, 2017 in Washington, DC. (Photo by Brendan Smialowski/AFP Photo)

U.S. President Donald Trump holds up a pen after signing the HBCU executive order in the Oval Office of the White House, in Washington, DC, U.S. February 28, 2017. (Photo by Yuri Gripas/Reuters)

A military parade is held to celebrate the 173rd anniversary of Dominican independence in Santo Domingo, Dominican Republic on February 27, 2016. Thousands of people enjoyed the activity along the coastal avenue in Santo Domingo. (Photo by Stringer/Anadolu Agency/Getty Images)

The Lord Mayor of London (C) joins others as they flip pancakes ahead of the annual Inter-Livery Pancake Race at The Guildhall on February 28, 2017 in London, England. The race sees 24 teams from London's traditional companies of craftspeople take part in a pancake-tossing race, while dressed in either their ceremonial robes or novelty costumes. (Photo by Leon Neal/Getty Images)

Competitors from the opposing teams, the Up'ards and the Down'ards, reach for the ball during the annual Royal Shrovetide Football Match in Ashbourne, northern England, on February 28, 2017. The mass-participation ball game involves two teams, whose players are defined by which side of a small brook that bisects the town they were born, aiming to score a goal, which are some three miles apart. The game, which has very few rules, is played over two 8 hour periods on Shrove Tuesday and Ash Wednesday. Royal Shrovetide Football is believed to have been played annually in Ashbourne since 1667. (Photo by Oli Scarff/AFP Photo)

The ball breaks from the hug during the annual Shrovetide football match in Ashbourne, Derbyshire, Britain, 28 February 2017. The game which dates back to the 17th century is played by two teams, the Up'ards and the Down'ards. The aim of the game is to score by tapping the ball three times on stone goal plinths which are three miles apart on the banks of the River Henmore. (Photo by Nigel Roddis/EPA)

David Harbour, Finn Burns and Ed Burns attend Toronto Raptors Vs. New York Knicks game at Madison Square Garden on February 27, 2017 in New York City. (Photo by James Devaney/GC Images)

This photo taken on February 27, 2017 shows pilgrims throwing items into a bonfire during a temple fair at the Tai Hao Tomb Temple in Huaiyang County in Zhoukou in China's central Henan province. Visitors and pilgrims from home and abroad gathered at the temple to pay homage to Tai Hao, one of the ancestors of the nation according to Chinese mythology. (Photo by AFP Photo/Stringer)

Israeli policeman grabs a young settler from the West Bank settlement of Ofra, Tuesday, February 28, 2017. Israeli forces began evacuating nine homes in the settlement following a Supreme Court decision that ruled they were built on private Palestinian land. (Photo by Oded Balilty/AP Photo)

Spanish activist Jil Love (R) and Mexican activist Julia Klug perform with tapes and fake blood during a protest against femicide and violence against women in Mexico City, Mexico February 27, 2017. (Photo by Carlos Jasso/Reuters)

A woman participates in a protest over the death of a hippo after an attack in San Salvador, El Salvador, February 27, 2017. (Photo by Jose Cabezas/Reuters)

Japan's Prince Akishino (R), his wife Princess Kiko (2nd L) and thier daughters Princess Mako (2nd L) and Princess Kako send off Emperor Akihito and Empress Michiko boarding a special flight for their visit to the Vietnam and Thailand, at Haneda Airport in Tokyo, Japan February 28, 2017. (Photo by Issei Kato/Reuters)

The fossil of a new plesiosaurus species, nicknamed Mauriciosaurus Fernandezi, is pictured during a news conference at the house of Mauricio Fernandez, mayor of San Pedro Garza Garcia, on the outskirts of Monterrey, Mexico February 27, 2017. (Photo by Daniel Becerril/Reuters)

A Palestinian Fatah member takes up a position in the Ain el-Hilweh Palestinian refugee camp in southern Lebanon, February 28, 2017. (Photo by Ali Hashisho/Reuters)

A slipper is seen amid bullet casings in the Ain el-Hilweh Palestinian refugee camp in southern Lebanon, February 28, 2017. (Photo by Ali Hashisho/Reuters)

K. Madhusudhana Sastry, father of Srinivas Kuchibhotla, an Indian engineer who was shot and killed in the United States last week, performs last rites of his son during his funeral at a crematorium in Hyderabad, India, February 28, 2017. (Photo by Reuters/Stringer)

An Indian student blows bubbles as she joins others during a protest march outside Delhi University against the Akhil Bharatiya Vidyarthi Parishad (ABVP) students wing of Bharatiya Janata Party (BJP) in New Delhi on February 28, 2017, after it was accused of attacking students, lecturers and journalists in the campus on February 22. (Photo by Sajjad Hussain/AFP Photo)

A protestor and police officer react during a march held on campus against violence and intimidation within Delhi University, India, February 28, 2017. (Photo by Cathal McNaughton/Reuters)

A man carries a mannequin dressed as U.S. President Donald Trump past supporters during a rally in favor of the “America First” on February 27, 2017 in Brea, California. Dozens of supporters of U.S. President Donald Trump held a rally outside the office of U.S. Rep. Ed Royce (R-CA) in support of the “America First” agenda that the Trump administration is pushing forward. (Photo by Justin Sullivan/Getty Images)

A woman dances as Arab and Jewish players compete in a backgammon championship organised by Double Yerushalmi, a group trying to build closer ties between Arabs and Jews through cultural activities, in Jerusalem February 27, 2017. (Photo by Ammar Awad/Reuters)

Visitors try an Xperia Touch by Sony during Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Eric Gaillard/Reuters)

A robot greets visitors during Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Eric Gaillard/Reuters)

A woman presents a E&L waterproof mobile phone during Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Eric Gaillard/Reuters)

New LG watch sport is displayed at Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Eric Gaillard/Reuters)

Old mobile phones are seen as part of an artwork on display at the Aptoide stand at the Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Paul Hanna/Reuters)

An exhibitor points to a display at the Zangi messenger app stand at the Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Paul Hanna/Reuters)

Commerce Bot, a robot that provides customer service with artificial intelligence technology and voice recognition is seen at SK telecom's stand at the Mobile World Congress in Barcelona, Spain, February 28, 2017. (Photo by Paul Hanna/Reuters)

Israeli soldiers are seen next to a tank, near Israel's border with the central Gaza Strip February 28, 2017. (Photo by Amir Cohen/Reuters)

Men unload boxes of nutritional supplements from an helicopter prior to a humanitarian food distribution carried out by the United Nations World Food Programme (WFP) in Thonyor, Leer county, South Sudan, February 25, 2017. (Photo by Siegfried Modola/Reuters)

A United Nations World Food Programme (UN WFP) helicopter flies over a queue of people waiting to be registered prior to a food distribution in Thonyor, Leer county, South Sudan, February 25, 2017. (Photo by Siegfried Modola/Reuters)

People take pictures as waves crash against the seafront of San Lorenzo beach in Gijon, northern Spain, February 28, 2017. (Photo by Eloy Alonso/Reuters)

A man reacts as waves crash against the seafront of San Lorenzo beach in Gijon, northern Spain, February 28, 2017. (Photo by Eloy Alonso/Reuters)

People react as waves crash against the seafront of San Lorenzo beach in Gijon, northern Spain, February 28, 2017. (Photo by Eloy Alonso/Reuters)

This handout picture received from the European Space Agency (ESA)/ North American Space Agency (NASA) on February 27, 2017 shows French Austronaut Thomas Pesquet juggling and eating “Macarons” which were specially modified for consumption in space by French master pastry chef Pierre Herme, aboard the International Space Station. Two boxes of seven macarons were baked delivered to Pesquet on the International Space Station in time for his birthday. (Photo by AFP Photo/ESA/NASA)

Green algae sits on a beach in Kuwait City, Kuwait, 28 February 2017. The formation of green algae is a normal phenomenon that occurs every year at the shores of Kuwait. (Photo by Raed Qutena/EPA)